If you find the idea of not having water available 24/7 every day except for the week they will be working on your unit un acceptable and your LL will let you out of your lease with zero penalty to you then that is a solution but I suggest you wait and have a talk with inspections , as far as a email goes to them , personally if it was me id go talk to them in person. ( you want to know if they can require the LL to have something installed to temporarily get water to units while they are replacing the pipes OR if they can require the LL to install valves that can shut off areas one at a time so the longest amount of down time would be when they replace the main lines that run from the meter to feed the individual units ? ) in the time being its time to leave for work. night.